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    He

    Helium

    Noble Gas

    Atomic Number: 2 • Atomic Mass: 4.0026 u • Period: 1 • Group: 18

    Electron Configuration: 1s²
    Phase: Gas
    Electronegativity: 0
    Hydrogen (H)Lithium (Li)
    OverviewPropertiesAtomic StructureOccurrenceApplicationsHistory

    Overview

    Helium is the chemical element with the symbol He and atomic number 2. It belongs to the Noble Gas group and is located in period 1 of the periodic table. It exists as a gas under standard conditions.

    Basic Information

    • Symbol:He
    • Atomic Number:2
    • Atomic Mass:4.0026 u
    • Group:18
    • Period:1
    • Category:Noble Gas
    • Phase at STP:Gas
    • Electronegativity:0 (Pauling scale)

    Key Facts

    Fun Fact #1

    Second most abundant element in the universe

    Fun Fact #2

    Cannot be solidified at normal atmospheric pressure

    Common Uses

    • Balloons
    • Cooling superconducting magnets
    • Deep-sea diving mixtures